Various styles of power-driven meat-cutting tools have been devised wherein a ring blade is rotatably mounted on a holder which in turn is mounted on a manually operated, power-driven handle or handpiece. These tools have been used for some time to facilitate the removal of meat from a carcass, primarily in a trimming operation or for removing the meat remains from the bones. These meat-cutting tools are either electrically or pneumatically driven. Some examples of these prior meat-cutting tools are shown in U.S. Pat. Nos. 3,269,010; 3,852,882; 4,170,063; 4,178,683; 4,198,750; and 4,324,043.
These power driven tools or trimming knives as they are generally referred to in the industry, consist of a tubular handpiece terminating in an arcuate shaped front end and formed with a hollow bore extending throughout the longitudinal length thereof. The annular blade holder is attached to the arcuate front end of the handpiece with the ring blade being removably mounted thereon by various mounting arrangements. The blade is formed with gear teeth extending around the top thereof, which are in driving engagement with a pinion gear rotatably mounted within the bore adjacent the front end of the handpiece.
In electrically driven knives a flexible cable, one end of which is connected to a motor located adjacent to the work area, enters the rear of the handle and extends through the bore and terminates in a squared end. The squared end is engaged in a complementary-shaped opening formed in the rear of the pinion gear for rotatably driving the gear. In pneumatically driven knives a squared shaft end of an air motor is engaged in the rear opening of the pinion gear for driving the gear.
These trimming knives have various size diameter blade holders and cutting blades mounted thereon depending upon the particular meat trimming operation for which the knives are to be used.
During the trimming operation, an operator draws the knife across the meat and sections or slices of meat are cut from the main body or carcass. The severed sections pass through the central opening of the blade housing and blade. It has been found that in using such knives, it is difficult to control the depth of the cut of the meat being removed. This results in increased cutting strokes or passes of the knife over the carcass to remove certain portions of the meat, such as in fatty areas, in contrast to other areas where too much lean meat is removed by a single movement of the knife across the carcass. This adversely affects the appearance of the trimmed surface of the meat and removes unwanted meat from the main body reducing the yield of higher quality, more expensive lean meat.
Therefore, the need has existed for a depth control gauge for mounting on such trimming knives in which the operator can preset the gauge to insure that the amount of meat cut from the carcass during each stroke is of a predetermined thickness. Examples of such prior art depth control gauges for such trimming knives are shown in U.S. Pat. Nos. 3,461,557; 3,688,403; 4,166,317; and 4,142,291. Although these prior depth control gauges do perform satisfactorily in certain trimming operations, they possess one serious disadvantage. Once the depth of cut has been manually set by the operator it remains constant until being readjusted by the operator. This readjustment requires the operator to stop the machine and cutting operation and is relatively time consuming.
It is desirable when trimming certain types of meat, especially those having a large amount of fat, that the depth control be inoperative so that deeper cuts and thicker slices of meat containing the greater amount of fat can be severed in a single movement across the carcass. This reduces the number of cutting movements thereby increasing the trimming speed. Also, when trimming the same carcass, once the fat areas have been removed, it is desirable that the depth control gauge become operative to insure that only the required thickness of leaner meat be severed from the carcass during each cutting movement.
There is no known depth control gauge for such meat trimming knives of which I am aware which enables the depth control to be adjusted whereby a predetermined slice thickness can be severed during each movement across the meat and which includes a mechanism for rendering the gauge inoperative, easily and quickly, without stopping the trimming operation.